The present invention relates to an arrangement of a cooking plate provided with a central hole having a movable temperature sensor therein.
Usually, automatically controlled cooking plates are provided with a temperature sensor which is mounted in a central hole in the cooking plate. The sensor is connected with a thin, cup-shaped plate the upper side of which being plane and in addition being essentially parallel to the cooking surface of the cooking plate. The thin plate is operated by spring means to a position in which the upper side of the plate projects above the cooking surface. By that the spring means will force the thin plate against the lower side of the cooking utensil being placed on the cooking plate. Thereby, a good transfer of heat from the cooking utensil to the thin plate will be insured.
The distance between the upper side of the thin plate and the surface of the cooking plate is determined by a shoulder situated in the central hole. The shoulder cooperates with an annular projection or the like. In U.S. Pat. No. 3,114,027 the temperature sensor is arranged in a cylindrical body having two co-axial parts of different diameter, said parts being axially separated. The part having the smaller diameter is situated closest to the cooking surface. The two parts are separated by a conical part which is directed towards the cooking surface and which cooperates with a conical should in the wall of the hole at some distance into the hole.
In the embodiment disclosed the U.S.-reference a centering of the temperature sensor can be had in order to minimize the influence from the surrounding part of the cooking plate. However, a disadvantage is that a vertical annular clearance develops between the temperature sensor and the wall of the hole and liquid and other impurities can enter and disturb the function of the sensor. In addition, the clearance is narrow and accordingly it is difficult to clean it.